The invention relates to a conveying device comprising a support frame, a conveying member that has at least two driven conveying belts that circulate in parallel to one another and a conveying fabric arranged between the conveying belts and having at least one support surface.
Conveying devices for bulk material are known in a plurality of configurations. The bulk material to be transported by the conveying device is placed at point A onto the endless circulating conveying member and transported to point B where the bulk material or other transported goods are dispensed. In order for the goods that are being transported not to fall laterally off the conveying member, the known conveying devices are provided with support parts that project past the plane of the support surface of the conveying member and are designed to retain transported pieces that threaten to fall off the conveying member.
European patent application 1 300 062 A1 discloses a conveying device of the aforementioned kind. The conveying devices of the aforementioned kind exhibit in general satisfactory transport efficiency. In the abutting area of the conveying fabric arranged between the conveying belts there is however the problem that material can slide into the gap between the conveying fabric and the conveying belts and can also be lost. Also, depending on the material to be transported it is possible that material to be transported or dirt particles collect in the abutting area and build a material deposit over time that causes the conveying fabric to bulge at the abutting area. In this way, the gap is enlarged to a hole which leads to greater losses. Also, an increasing material deposit can in the end lead to the conveying fabric to be torn; an exchange is then required.
The support parts can be fixedly attached to the support frame. In such an arrangement, there is however the disadvantage that the material to be transported scrapes across the support parts and is therefore slowed down. This leads to efficiency losses, and the transported material itself has the tendency to stay behind because of the braking effect and, in the case of a slanted conveying path, to roll down. Moreover, sensitive material to be transported, for example, harvested material, can become damaged by the support parts by friction or by being jammed.
In order to prevent these disadvantages, the support parts are often fastened directly to the endless circulating conveying member so that the support parts move at the same speed as the transported goods conveyed on the conveying member. In such an arrangement, the support parts no longer scrape across the transported goods. At locations where the conveying direction of the conveying member changes, the support parts are however compressed or expanded. At the abutting locations between the support surfaces and the conveying belts or the support parts, gaps are generated through which gaps the transported goods can fall from the conveying member and can be lost.